With the rapid development of the semiconductor industry, people find that there are more requirements on the number of power supplies and power. Formerly, 3 to 4 power supplies may be enough for a system, and now there may be 10 to 20 or more power supplies. However, a time sequence for powering on and powering off the 10 to 20 or more power supplies is different, and power values are also different. Therefore, power management needs to be performed.
Power management bus (PMBus) is an open standard digital power management protocol, and may promote communication with a power converter or another device by defining transmission, a physical interface, and a command language. This protocol is established by a group of power supply and semiconductor manufacturers who think that the improvement of a solution of full digital power management is restrained due to a lack of a proper standard. At present, this protocol is being rapidly accepted by the industry.
As a management interface of a power supply chip, the PMBus is more widely used in a current integrated circuit system. A multi-output scenario in which multiple master devices (Masters) control a power supply chip in a same slave device is used as an example. The PMBus includes a data bus and a clock bus, and each Master is connected to the data bus and the clock bus. A PMBus command is sent to the power supply chip by using the data bus and the clock bus, and then the power supply chip is controlled, so that the power supply chip outputs corresponding voltage or implements another operation. A PMBus bus is an Inter-Integrated Circuit (I2C) serial bus; therefore, a data conflict may occur when multiple Masters are running at the same time. For example, two masters Master 0 and Master 1 are running at the same time. When detecting that the bus is idle, the two masters may send data to the power supply chip at the same time. At this moment, the PMBus initiates arbitration and determines which one between the Master 0 and the Master 1 is qualified to control the bus to perform data transmission, and data of a Master failed in the arbitration is discarded.
For the foregoing problem, an operation of the master failed in the arbitration may be discarded in the prior art, and the data is resent by using hardware; or an alarm is reported, then a command of resending the data is delivered by using software, and then the data is resent.
The prior art has at least the following problem. When a data conflict occurs in the multiple Masters, if the data is directly resent by using the hardware or the software, the resent data may still continuously conflict with each other, which may cause that a system cannot run normally, thereby seriously affecting reliability of the system.